A Libyan militia holding the younger brother of the Manchester Arena bomber says it is "ready to cooperate" with a extradition request from the UK.
Anti-terror police confirmed that an extradition request was handed to the authorities in Libya on Wednesday where Hashem Abedi is now in custody.
Both he and his brother Salman travelled to the country in April, before the latter returned to the United Kingdom alone.
The Deterrence Force - an armed militia allied to the UN-backed government in Tripoli - initially rejected the request.
Officers want authorities in Libya, where's Hashem Abedi's being held in custody, to extradite him to the UK.
Police have previously said they do not think Salman Abedi was part of a wider network but they believe others were involved in the planning of the attack and named Hashem as a suspect.
Hashem Abedi is the brother of Salman Abedi, who set off the bomb at the end of an Ariana Grande concert on May 22 that left 22 dead and hundreds wounded.
On Wednesday, police revealed that more than 500 people were injured in the terror attack. Injuries include burns, loss of limbs, paralysis and severe internal injuries.
Libyan authorities are considering the UK's formal request, Greater Manchester Police (GMP) has said.
Five months on, some remain in hospital.
Reacting to the news, Security Minister Ben Wallace said the Manchester attack was a "callous and evil act", adding: "the victims and their families deserve and demand justice".
Andy Burnham, mayor of Greater Manchester, said it is "imperative" that any trial related to the Manchester Arena attack takes place in the UK.